docs: def get_revocation_key(self, user):
          """
          When the value returned by this method changes, this revocates tokens.
  
          It always includes the password so that changing the password revokes
          existing tokens.
  
          In addition, for one-time tokens, it also contains the last login
          datetime so that logging in revokes existing tokens.
  
          """
          value = ''
          if self.invalidate_on_password_change:
              value += user.password
          if self.one_time:
              value += str(user.last_login)
          return value